20700690 has 64 divisors (see below), whose sum is σ = 54604800. Its totient is φ = 4999104.

The previous prime is 20700677. The next prime is 20700697. The reversal of 20700690 is 9600702.

It is a super-2 number, since 2×20700690² = 857037132952200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20700690.

It is not an unprimeable number, because it can be changed into a prime (20700697) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12321 + ... + 13899.

It is an arithmetic number, because the mean of its divisors is an integer number (853200).

Almost surely, 2^20700690 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20700690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27302400).

20700690 is an abundant number, since it is smaller than the sum of its proper divisors (33904110).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20700690 is a wasteful number, since it uses less digits than its factorization.

20700690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1631.

The product of its (nonzero) digits is 756, while the sum is 24.

The square root of 20700690 is about 4549.8010945535. The cubic root of 20700690 is about 274.5753887976.

The spelling of 20700690 in words is "twenty million, seven hundred thousand, six hundred ninety".